Objective To explore the clinical effect of comprehensive treatment for oral ulcer in children. Methods A total of 92 children with oral ulcer admitted to our hospital from January to October 2022 were randomly divided into control group and observation group, with 46 children in each group. The control group was given symptomatic and supportive treatment, and the observation group was combined with pediatric medicine for comprehensive treatment on this basis. The clinical efficacy, pain score, eating time, wound healing time and adverse reactions were compared between the two groups. Results The total effective rate of treatment in the observation group was 97.83%, which was higher than 84.78% in the control group (P<0.05). The VAS score of the observation group was lower than that of the control group, and the eating time and wound healing time were shorter than those of the control group (P<0.05). The incidence of adverse reactions in the observation group was 0, which was lower than 10.87% in the control group (P<0.05). Conclusion Comprehensive treatment for children with ulcers can effectively control infection, accelerate wound healing, reduce pain, promote granulation tissue formation, eat early, increase immunity, and reduce the incidence of adverse reactions. It is worthy of clinical application.